MECHANISM OF ACTION
- hypnotic & anticonvulsant
- depression of post-synaptic sensitivity to neurotransmitters & impairment of pre-synaptic transmitter release.
- molecular level unknown – may act like LA.
- inhibit Ca2+ dependent tranmitter release
- hygroscopic yellow powder
- thiopentone sodium (weak acid)
- 6% sodium carbonate
- stored under atmosphere of nitrogen (see later)
- reconstituted with H2O
- produces a 2.5% solution
- IV or PR
- IV – 3 – 7mg/kg -> acts within 1 arm-brain circulation time, lasts for 5 to 15min
- PR – 1g/22 kg body weight -> acts within 15min.
(1) induction of anaesthesia
(2) treatment of status epilepticus
(3) brain protection
- increased infection risk
- accumulation -> inability to assess neurology in a timely manner
- negative inotrope
- extravasation -> necrosis
- Distribution – 80% protein bound, Vd 2L/kg
- Metabolism – hepatic
- Elimination – urinary, long T1/2